TIRE RUBBER IN HOT MIX ASPHALT PAVEMENTS

In 1989 and 1993, the Wisconsin Department of Transportation (WisDOT) initiated two separate research studies to evaluate (1) the effectiveness of a rubberized asphalt binder mixed with a virgin aggregate gradation for use as an overlay and/or a stress absorbing interlayer, and (2) the recyclability of a reclaimed asphaltic pavement (RAP) containing tire rubber. These studies are presented in this report. Numerous test sections and control sections, of different pavement designs, were constructed for performance evaluations and comparisons. The results and conclusions of the studies are summarized as follows: The construction of the crumb rubber modified (CRM) hot mix asphalt (HMA) pavement and the recycled CRM RAP went fairly smoothly; only minor complications were encountered, primarily due to lack of experience with paving CRM asphaltic mixes, and were easily overcome. Emission data showed that recycling a pavement that contains tire rubber does not appear to pose a threat to the health of the workers or to the environment. All test sections performed comparably with their respective control sections, and no individual test section/pavement design clearly outperformed all others. The inclusion of crumb rubber into a virgin HMA pavement for use as an overlay or as an interlayer did not enhance or impede the overall performance of the pavement, in comparison to a virgin HMA pavement. The RAP mix containing tire rubber was successfully recycled and performed similarly to a new HMA pavement. The asphalt rubber did not appear to increase or decrease the amount or rate of reflective cracking. The inclusion of crumb rubber increased the cost of the rubberized asphalt binder by 76% to 271%, and the CRM mixes by 52% to 117%. A CRM HMA interlayer increased the project cost by approximately $10,000 per lane-mile. Cost savings were achieved when the CRM RAP was milled for recycling, as pavements constructed with RAP are generally less expensive than pavements constructed with virgin materials. With performances similar to standard HMA pavements and higher costs, WisDOT's CRM HMA pavements have not proven to be cost-effective.

• Record URL:
  http://wisdotresearch.wi.gov/wp-content/uploads/wi-06-02tirerubber.pdf
• 
• Corporate Authors:

  Wisconsin Department of Transportation

  Bureau of Highway Construction, 3502 Kinsman Boulevard
  Madison, WI  United States  53704

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Bischoff, D
  • Toepel, A
• Publication Date: 2004-5

Language

• English

Media Info

• Features: Appendices; Figures; Photos; Tables;
• Pagination: 60 p.

Subject/Index Terms

• TRT Terms: Asphalt pavements; Asphalt rubber; Cost effectiveness; Costs; Crumb rubber; Environmental impacts; Hot mix asphalt; Occupational safety; Overlays (Pavements); Pavement performance; Recycled materials; Recycling; Reflection cracking; Test sections
• Uncontrolled Terms: Scrap tires; Stress absorbing interlayers
• Subject Areas: Design; Environment; Finance; Highways; Materials; Pavements; Safety and Human Factors; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 00975845
• Record Type: Publication
• Report/Paper Numbers: WI-06-02,, Final Report
• Files: TRIS, USDOT, STATEDOT
• Created Date: Jul 8 2004 12:00AM